Rock-drill



A. ALFORD.

ROCK DRILL- APPLICATION FILED JULY 28. I920.

1,387,447, Patented Aug. 16, 1921.

UNlTlZD, STATES PATENT. OFFICE;

' ALEORD, OI WACO, TEXAS.

' ROCK-DRILL.

Application filed July 28, 1920. se rial no. ae9,4s3.

To all whom it may com-m; Be it known that I, ALLEN ALFORD, a citizen of the United States, residing at Waco, in the county of McLennan and State of Texas, have invented pertainnewand useful Improvements in Rock-Drills, of which the following is a specification.

This invention relates to improvements in ticularly to a rock drill and to the arrangement and constructionof such a drill.

The principal objectof the invention is to provide an improved drill for quickly boring or cutting through hard formationssuch as rock, sandstone and the like, the drill being provided with 'cutting sur faces for cutting or boring through these formations according. to their degree of hardness. Other improved features such as the ready removal of the drill-parts and means for alfixing these parts in the drill body will be referred to in the following description and accompanying drawings wherein- Figure 1 is aside elevational view of adrill body illustrating my invention.

. Fig. 2 is a vertical sectional view.

Fig. 3 is a cross sectional view taken on line 3-3 of Fig. 1.

Fig. 4 is a top view of the end or drill bit removed from the body, and

Fig. 5 is a fragmentary detail sectional view of a modified arrangement of theblades in the drill body.

Referring more particularly to the drawings, 1 denotes thedrill body which is of frusto-conical formation and centrally bored for the water line 2 and provided with a screw-threaded recess indicated at 3 for the reception of a drill bit& which is also een- -40 trally bored to provide a continuation of the water line 2. The water line 2 extends to withina short distance of the end ofthe bit 4 where it is reduced in diameterinto the radials 5 5 and a lower outlet.6. The drill bit 4 as will be noted by reference to Figs. 1 and 4 is cone-shaped and has its outer surface corrugated or roughed in the form of the ridges or ribs 7-7 to bite into the sandstone or other stratum. As the outer surface wears away the nose or point 8 is kept 'continually sharpened by reason of the fact that" when the outer or ribbed surface of the bitis worn inward the wall of the outlet 6 will .form a sharp edge or point with the outer surface or ribs 7-7.

.Slots traversing the body 1 from side to Specification of Letters Patent.

Patented Aug. 16', '1921.

side are provided for receiving the blades 99. These blades as will be noted by reference to igs l and 2 project through the body at right angles 'to each other. The ends of the-blades have an angular parallel relationship :to the body 1, each blade being increased in-length from the bottom to the top -of the body, sothat its projecting ends will extend outward from the body the same distance in an upwardly increasing ratio. The blades are locked in position by set screws 10-10. The lowermost blade when in posi-v tion locks the drill bit 4 in the body as this blade, see Fig. 2, rests in the slots'1111, see also Fig. 4.

The drill bit 4. will bore into the hard strata and as the hole is deepened the lower- I most. of the blades 9-9 will take hold to increase the diameter of the hole and so on upward 'until the' topmost blade is reached Where the full diameter is attained. On account of the conical formation'of the drill body'and its blades a hole in, hardformation.

can be more quickly bored as is obvious than if the blades and body were on vertical parallel lines.

Where. the formation in the well is very hard .I have provided a modified form of blade, illustrated in Fig. 5. In this form the shoulder of the blade is flush with the surface of the body 1 and has a small protuberance 12v with. its end on an angle with the body. A roller 13 with a corrugated or ribbed outer face 14 andedges 15 is rot'atably mounted upon the protuberance 12 and held to positionby a screw or axis 16. This form of blade with rollers is held in the body 1 by set screws similar to the blades shown in Fig. 2, it being only necessary to remove the set screws 10 and the rollers 13 when insert drill body from side to side through the body, meansfor locking the drill'bit in position in the body to one of the blades, and channels for a water linein the body and bit.

2. A drilling tool for wells for boring rock and similar hard formations, comprising a conoidal shaped drill body and a conical bit on oneend thereof, a plurality of supporting members placed through the drillbody from members in the body and for locking the drill side to side and extending from the top to bit in the body and onto the lowermost supthe bottom of the body fromoppositesides porting member. I of the body and extended beyond the periph- In testimony whereof I have signed my 5 ery of the body, corrugatedly surfaced rotanameto this specification. table rollers on the ends of the supporting 7 members, means for securing the supporting 7 I ALLEN ALFORD. 

